Message-ID: <442C25D0.7030605@pondol.com>
Date: Thu, 30 Mar 2006 12:39:12 -0600
From: David Carter <carter AT pondol DOT com>
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To: cygwin AT cygwin DOT com
Subject: problems with gawk 3.1.5-3 hanging
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Hi all:

First, I found another gentleman with a similar issue in the mailing 
list archive:

http://www.cygwin.com/ml/cygwin/2006-03/msg00425.html

Seems he thought the problem wasn't with gawk 3.1.5-3 in the end, 
however I'm having very similar issues with gawk hanging and it only 
happens with 3.1.5-3. When I revert to 3.1.5-2, the problem seems to go 
away.

Unfortunately, the issue is intermittent and only seems to occur when i 
call gawk from the bowels of my fairly long bash script. When I try to 
isolate the problem by running the same gawk script manually from a 
prompt, the problem disappears. Perhaps this is related to why the other 
poster became convinced the problem wasn't actually with gawk, when in 
fact it the problem was with gawk, but hard to pin down.

The gawk script in question is very simple and is meant to reduce the 
output from an rsync transfer. Here's a snippet:

rsync -vP sourcefile remotesys:~/remotefile | gawk \
'
BEGIN {
	RS="\r|\n";
	FS=" ";
}

{
	if ( $2 ~ /\%/ ) {  # if field 2 contains a percent sign
		if ( FNR % 10 == 0 || $5 ~/\(/ ) {
		# if its the tenth line, or field 5 contains a "("
			print $0;
			fflush();
		}
	} else {
		print $0;
		fflush();
	}
}
'

Again, if I run this command from a prompt, it works (with 3.1.5-3 and 
3.1.5-2). But when called from the bowels of a longer shell script (not 
included for brevity), it usually (but not always) hangs with 3.1.5-3. I 
can verify the rsync transfer finishes properly, but gawk never exits 
and I don't get all the output that I should to stdout, either. I don't 
see anything going to stderr. Again, it works 100% of the time with 3.1.5-2

Does anyone have some pointers on how I can further debug this? I'd like 
to forward more information to the appropriate parties.

Regards;

David Carter


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